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'Dragons' of the Gamms-Ray Sky



 
 
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  #1  
Old March 8th 10, 10:13 PM posted to sci.astro.research
Robert L. Oldershaw
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Default 'Dragons' of the Gamms-Ray Sky

Be sure to check this out!

http://www.sciencedaily.com/releases...0302162505.htm

It has long been assumed that the diffuse Gamma-Ray background was
dominated by active galaxies like blazars, quasars, Seyferts, etc.

Now comes a dramatic result from the Fermi team that appears to reject
that assumption, and leaves a very important question in its place.

The Fermi team reports ( http://arxiv.org/PS_cache/arxiv/pdf/...002.4415v1.pdf
) that only about 1/3 of the diffuse Gamma-ray background comes from
active galaxies. That leaves 2/3 of the background being produced by
unknown entities.

Two possible explanations for the unknown source population are as
follows.

[Mod. note: to save time and electrons, let me be the first to point
out that there are probably more than two in total -- mjh]

(1) The radiation could be generated by hypothetical annihilations of
hypothetical WIMPS (good luck with that one).

(2) Alternatively, contrary to current assumptions, there could be a
roughly isotropic distribution of stellar-mass black holes in the MWG
halo that emit very high energy jets of particles which, in turn,
generate Gamma-rays. In this scenario, all galactic haloes would
contribute to the Gamma-ray background too.

Note that a large populaton of stellar-mass black holes in more
quiescent states would be a nice candidate for the Long Duration Radio
Transients and the anomalous radio background discovered in the ARCADE
observations.

Perhaps nature is sending us many hints: X-ray Ridge discrete sources,
LDRTs, RRATs, Gamma-ray background, microlensing-detected MACHOs,
Gamma-ray burst sources, pulsars, quiescent neutron stars, compact
central objects in SN remnants?

One general class of stellar-mass ultracompact objects with masses
primarily in the 10^-4 to 2.0 solar mass range would explain quite a
number of enigmatic results.

RLO
www.amherst.edu/~rloldershaw
  #2  
Old March 10th 10, 12:42 PM posted to sci.astro.research
Phillip Helbig---undress to reply
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Posts: 629
Default 'Dragons' of the Gamms-Ray Sky

In article , "Robert L.
Oldershaw" writes:

(2) Alternatively, contrary to current assumptions, there could be a
roughly isotropic distribution of stellar-mass black holes in the MWG
halo that emit very high energy jets of particles which, in turn,
generate Gamma-rays. In this scenario, all galactic haloes would
contribute to the Gamma-ray background too.


Why should anyone believe this if no TESTABLE PREDICTION indicating such
radiation was made BEFORE the observation? One can always take any
observation and say that, maybe, contrary to current assumptions, some
object is responsible for it. But that's not science. Maybe there are
angels whose moving wings radiate gamma rays. That's an explanation in
the same league.

One general class of stellar-mass ultracompact objects with masses
primarily in the 10^-4 to 2.0 solar mass range would explain quite a
number of enigmatic results.


Perhaps, but it has been RULED OUT due to the lack of a PREDICTED
signature in QSO light curves.
  #3  
Old March 12th 10, 10:05 AM posted to sci.astro.research
Kent Paul Dolan
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Posts: 225
Default 'Dragons' of the Gamma-Ray Sky

Robert L. Oldershaw wrote:

So why do so many astrophysicists assume the dark
matter is composed of WIMPs, or even more exotic
particles, while very few astrophysicists
entertain the possibility that the observed
stellar- mass ultracompacts might be the
proverbial tip of the dark matter iceberg?



Which part of Phillip's "ruled out by evidence" do
you have trouble understanding? He's told you that
at least twice.

You keep trying to sneak your "dark stars as the
dark matter" in one way or another, but the evidence
has already eliminated them.

This gets tedious.

Could you find another hobby?

xanthian.
  #4  
Old March 12th 10, 09:04 PM posted to sci.astro.research
David Staup
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Posts: 358
Default 'Dragons' of the Gamma-Ray Sky

"Kent Paul Dolan" wrote in message
...
Robert L. Oldershaw wrote:

So why do so many astrophysicists assume the dark
matter is composed of WIMPs, or even more exotic
particles, while very few astrophysicists
entertain the possibility that the observed
stellar- mass ultracompacts might be the
proverbial tip of the dark matter iceberg?



Which part of Phillip's "ruled out by evidence" do
you have trouble understanding? He's told you that
at least twice.

You keep trying to sneak your "dark stars as the
dark matter" in one way or another, but the evidence
has already eliminated them.

This gets tedious.

Could you find another hobby?

xanthian.


can you provide links to this evidence?

a curious amateur
  #5  
Old March 14th 10, 11:54 AM posted to sci.astro.research
Richard D. Saam
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Posts: 240
Default 'Dragons' of the Gamms-Ray Sky

On 3/8/10 3:13 PM, Robert L. Oldershaw wrote:

The Fermi team reports ( http://arxiv.org/PS_cache/arxiv/pdf/...002.4415v1.pdf
) that only about 1/3 of the diffuse Gamma-ray background comes from
active galaxies. That leaves 2/3 of the background being produced by
unknown entities.



A large question is whether the peak at 56 Mev (figure 4)
EGRET (Sreekumar et al. 1997)
EGRET (Strong et al. 2004)

is confirmed by further data analysis extending
Fermi (Abdo et al. 2009) (figure 4)
to that 56 Mev peak range.

Why the peak?
and
why the near constant log slope with increased energy?

This is a 'noisy' area of the FERMI platform and will take more data
analysis time.

I think the answer is extremely fundamental.

Richard D. Saam
  #6  
Old March 14th 10, 06:37 PM posted to sci.astro.research
Phillip Helbig---undress to reply
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Posts: 629
Default 'Dragons' of the Gamma-Ray Sky

In article , "Robert L.
Oldershaw" writes:

So why do so many astrophysicists assume the dark matter is composed
of WIMPs, or even more exotic particles, while very few
astrophysicists entertain the possibility that the observed stellar-
mass ultracompacts might be the proverbial tip of the dark matter
iceberg?


Because compact stellar-mass objects, regardless of what they are
composed of (we know they can't be baryonic because of constraints from
primordial nucleosynthesis), make a definite prediction. They will
cause microlensing of QSOs with a clear observational signature. There
are a lot of observations of QSO variability, and microlensing theory is
well understood, and the predictions do not correspond to the
observations. End of story.

That (some) QSO variability is due to microlensing and that this could
be a sign of dark matter was a good theory in that it made testable
predictions. But if those predictions were falsified, i.e. ruled out by
observations, then the theory needs to go.

The steady-state theory was in this sense a good theory. It was ruled
out. Fred Hoyle, Geoff Burbidge and others tried to save it with ever
more epicycles. Other people, such as Philip Morrison, moved on.
  #7  
Old March 14th 10, 06:41 PM posted to sci.astro.research
Phillip Helbig---undress to reply
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Posts: 629
Default 'Dragons' of the Gamma-Ray Sky

In article , "David Staup"
writes:

"Kent Paul Dolan" wrote in message
...
Robert L. Oldershaw wrote:

So why do so many astrophysicists assume the dark
matter is composed of WIMPs, or even more exotic
particles, while very few astrophysicists
entertain the possibility that the observed
stellar- mass ultracompacts might be the
proverbial tip of the dark matter iceberg?


Which part of Phillip's "ruled out by evidence" do
you have trouble understanding? He's told you that
at least twice.

You keep trying to sneak your "dark stars as the
dark matter" in one way or another, but the evidence
has already eliminated them.


can you provide links to this evidence?


Back in 1996, the jury was still out (even then, Oldershaw was getting
plenty of responses to his ideas):

http://groups.google.de/group/sci.as...0a0b24fbc36b55

More evidence was in by the end of 2006, and your idea was looking worse:

http://groups.google.de/group/sci.as...51f8625c33577f

Just a couple of months ago, the nail in the coffin with a link to a
paper which appeared in A&A:

http://groups.google.de/group/sci.as...d81f9277023f52

I haven't seen you react to this paper at all. To my knowledge, no-one
has published a paper demonstrating it is wrong, whereas many papers
were published demonstrating why compact stellar-mass objects cannot be
the lion's share of dark matter.

Ignoring the evidence and touting the same hypothesis for decades
despite the evidence is not good science.
 




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